1. Field of the Invention
This invention relates to one-way or check valves and, more particularly, to such valves for use as inflation valves employed with catheters.
2. Description of the Prior Art
Catheters have a variety of uses in conducting fluids to or from body cavities. In many cases catheters are provided with a cuff including an inflatable balloon suitable for engaging and sealing the wall of a body passage so as to limit passage of fluid to or from the body cavity to that passing through the catheter. For example, a tracheal catheter may be designed for insertion through the trachea and may include an inflatable balloon near the distal end for engaging and sealing the tracheal passage.
It is important that the balloon be easily inflated and that it remain in the inflated condition for the desired length of time. For example, a tracheal catheter may be employed in connection with a surgical procedure extending over a significant period of time, and it is necessary that the balloon remain reliably inflated throughout this time.
For this purpose it is conventional to provide a one-way, or check, valve in a tube connected to the balloon for inflation thereof. It is desirable that this check valve, which in this specification will hereafter also be referred to as an inflation valve, be easily actuated when it is desired to supply fluid to the aforementioned balloon of the catheter or when it is desired to discharge the fluid therefrom, and it is desirable that the valve remain reliably sealed during the intervening period.
It is increasingly common that catheters of this type are intended to be disposable after a single use. Accordingly, it is desirable that such devices be of simple construction and be inexpensive to manufacture. These requirements, of course, apply to the inflation valve which forms part of the disposable catheter. Many prior art inflation valves have involved three or more parts and have involved significant cost in manufacture and assembly. The prior art does include some two-piece inflation valves but these prior art two-piece valves have involved manufacturing and assembly problems which increased the cost and make them less desirable, therefore, for use as disposable items.
The valve of the present invention employs a highly simplified two-piece construction which enables the components of the valve to be manufactured easily and at low cost and which is constructed so as to make the assembly of the two parts of the valve simple and easy. Further, the construction is such that the valve element seats firmly so as to insure against undesired leakage of fluid therethrough but is easily moved to its open position when desired so as to provide for passage of fluid.
Accordingly, it is an object of this invention to provide a check valve, particularly for use as an inflation valve in a disposable catheter, which is simple and economical in construction and assembly.
It is a further object of this invention to provide such a valve which is formed from a minimal number of parts.
It is still another object of this invention to provide such a valve which, despite its simplicity and low cost, is effective in preventing leakage of fluids.